I'm able to edit listing from Chrome on Windows. If it's urgent for you, why don't you try editing from the Airbnb App? Worth giving a shot if it works 🙂
I have tried doing that now on my iPad to edit my calendar, and for some reason when I save changes to block out a date it doesn't persist... I think something is messed up perhaps with my listing and not sure what to do 😞
I've seen multiple questions today regarding the Site features not working. There's probably a glitch, Airbnb might be pushing some updates. You might want to wait for 24 hours and try again.